Well he was loyal to konoha and he knew that if the Uchia were to take cotrol alot of people would die. So he did what was necessary. This doesnt mean he hated the Uchia, because if he did hate them he wouldnt have left his little brother to clear their name(even though it all went wrong with the Sasuke wanting revenge on Konoha thing).

i think he did the right thing becouse otherwise Uchiha would start war inside the village and that would weakened the whole village and other nations could attack them and even start the 4th ninja war...
he made a mistake leaving sasuke alone cuz he became STUPID and is now trying to destroy everything that Itachi died for

Hey i agree with you in a way and in another way, i think what he did makes sense. i mean if they started a war 2 many people would die for just one clan, but also on the other hand, what Konoha was doing to the Uchihas was wrong, i mean they were extrodinary ninjas and at the same time konoha ninjas. Konoha was discriminating because the uchihas were powerful ninjas. anyway even if he didnt kill them, konoha ninjas would, so he killed everyone but his brother, so that his brother would revive the clan, as a proud clan from Konoha.
God i hope i make sense.

The thing is that Konoha had no choice I mean the Akatsuki clan was going to start a war there was no way to stop it and since the only loyal to Konoha was Itachi and he knew both side's story he had to make a choice and he made the right one even though it condemned him to a life of solittude.